采用浸渍法制备了MoO3/ZrO2, 用低温氮吸附-脱附法和NH3-程序升温脱附法(TPD)分别对其比表面积和酸碱性进行了表征. 结果表明, MoO3/ZrO2具有106.8m2/g的比表面积和超强酸的性能. 用等体积浸渍法制备了Pt/MoO3/ZrO2催化剂, 在汽车尾气模拟气中考察了其对C3H8、CO和NO的催化活性.与传统三效催化剂Pt/La2O3/Al2O3相比较, Pt/MoO3/ZrO2具有更好的低温起燃性能和更宽的空燃比窗口, 并显著地改善了C3H8在富氧状态下的转化效率. 通过XRD、H2-TPR对催化剂进行了表征, 结果表明, Pt在催化剂载体上具有高度的分散性和优异的氧化还原性能.
MoO3/ZrO2 was prepared by impregnation method. Its specific surface area, pore size, pore volume and surface acidity were investigated by means of low temperature nitrogen adsorption-desorption and NH3-temperature programmed desorption. By using MoO3/ZrO2 and La2O3/Al2O3 as catalyst support, Pt/MoO3/ZrO2 and Pt/La2O3/Al2O3 catalysts were prepared by wet impregnation method and the activity test of C3H8, CO, NO were also investigated in the simulated automotive gas. The results show that MoO3/ZrO2 has good texture(SBET=106.8m2/g) and surface super-acidity. And the catalysts were also characterized by X-ray diffraction and H2-temperature programmed reduction. Compared with traditional three-way catalyst Pt/La2O3/Al2O3, Pt/MoO3/ZrO2 exhibits lower light-off temperature of hydrocarbon (230℃), carbon monoxide (200℃), and nitrogen oxides
(210℃) and wider operational air-to-fuel ratio window, which especially improves C3H8 conversion under higher oxidative conditions. The results also show that Pt on the catalyst support has high dispersion and excellent redox properties.
参考文献
| [1] | Gandhi H, Graham G, McCabe R. Journal of Catalysis, 2003, 216 (1-2): 433-442. [2] Jen W, Gramham W, Chun W, et al. Catalysis Today, 1999, 50 (2): 309-328. [3] Kaspar J, Fornasiero P, Hickey N, et al. Catalysis Today, 2003, 77 (4): 419-449. [4] 张昕, 贺德华, 张起俭, 等. 催化学报, 2003, 24 (1): 22-26. [5] Vrinat M, Hamon D, Breysse M, et al. Catalysis Today, 1994, 20 (2): 273-282. [6] Tanaka T, Yokota K, Isomura N, et al. Applied Catalysis B: Environmental, 1998, 16 (3): 199-208. [7] García-Cortés J, Pérez-Ramǐrez J, Illán-Gomez M, et al. Applied Catalysis B: Environmental, 2001, 30 (3-4): 399-408. [8] Komandur V, Kondakindi R, Gurram K, et al. Journal of Catalysis, 2004, 226 (2): 283-291. [9] El-Sharkawy E A, Khder A S, Ahmed A I. Microporous and Mesoporous Materials, 2007, 102 (1-3): 128-137. [10] Yang Zhuxian, Chen Xiaoyin, Niu Guoxin, et al. Applied Catalysis B: Environmental, 2001, 29 (3): 185-194. [11] 辛勤. 固体催化剂研究方法(上册), 第一版. 北京: 科学出版社, 2004. 277-232. [12] 喻瑶, 林涛, 张丽娟, 等(YU Yao, et al). 无机材料学报(Journal of Inorganic Materials), 2008, 23 (1): 71-76. [13] Fernández-Garecía M, Martínez-Arias A, Rodriguez J. Chemical Review, 2004, 104 (9): 4063-4104. [14] 郭家秀, 龚茂初, 袁书华, 等. 中国稀土学报, 2006, 24 (1): 27-31. [15] He H, Dai H X, Ng L H, et al. Journal of Catalysis, 2002, 206 (1): 1-13. [16] Belokopytov Yu V, Kholyavenko K M, Gerei S V. Journal of Catalysis, 1979, 60 (1): 1-7. [17] 王学中, 杨向光, 吴越. 催化学报, 1998, 19 (3): 191-195. |
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